1983 Johnson 140 J140TLCTE: No power to plane up

[out 2 launch]

Originally posted by racerone View Post
Any chance the nieghbors pet mice built a nest in the exhaust housing ???
I think racerone may be on to something that should be considered. I have experienced similar problems with outboards though not of this size (140 hp). My experience involved 25-40 hp outboards and is even more common with smaller two strokes such as chain saws and trimmers. Synopsis: Motor lacks power at increased throttle but starts and idles fine. The power loss is smooth without any noticeable miss or surging. Compression, ignition and fuel delivery all check out OK. What I have found when all else seems to check out ok and something still is amiss check the exhaust system for obstruction. I have found that where the inner exhaust housing meets the adapter plate most commonly at its narrowest area or at its sharpest bend carbon will accumulate and start to build up. This in turn restricts exhaust flow resulting in power loss. Just a possibility.

 

[Big Fish Billy]

I just bought a 1990 Wellcraft CC with a 1993 150 Oceanrunner. The PO described your exact circumstances and his buddy/outboard mechanic diagnosed the problem and replaced the power pack and solved the problem, the boat goes near 50 now...don't know if your new power pack might have been defective or have blown again. I would test that....http://www.ehow.com/how_8726514_check-pack-johnson-outboard-motor.html

 

[emdsapmgr]

You said you replaced the pack. There are two on that engine-were both replaced? It's possible that the engine will make good spark when on the trailer. Weak or faulty ignition components tend to break down once the engine heats up to normal operating temps, such as then you have it in the water and it's run for 20 minutes and is under load. Do your drop test when it's warmed up and under load. Or use an inductive timing light on each plug wire when under load. The flashes from the gun will show misfires, intermittents, etc. The rectifier is part of the engine's charging system and has no bearing on the ignition system.

 

[Big Fish Billy]

Good point on the rectifier/regulator, are your batteries charging properly 13.49 volts at least. If the batteries aren't at 12.67 volts at starttup, you may not be getting good voltage to anything....

 

[kevwinpal]

We took the engine out today to do the drop test. Turns out I didn't need to as the engine ran fine.

The problem I believe was a loose electrical connection from the power pack to the ignition coils.

I don't fully know if that was it but I think it was.

Heres a link to a video of it running perfectly. The spark advance lever sticks a little but I can fix that.

Its a Johnson 140 1983 J140TLCTE. As old as me. 32 years.

https://drive.google.com/file/d/0B3dfMH_Vd3LEc3V0YVlQamxtR00/view?usp=sharing